Antenna



FIG. 1 is a front view illustrating an antenna;

FIG. 2 is a left view of the antenna;

FIG. 3 is a right side view of the antenna;

FIG. 4 is a top side view of the antenna;

FIG. 5 is a rear view of the antenna; and,

FIG. 6 is a bottom view of the antenna. 

CLAIM The ornamental design for an antenna, as shown and described. 